That's it? All right.
This gives me a chance then to pop in and just ask for a little additional clarification.
You mentioned that the groups in some cases avoid combat with each other and exploit the population, which raises two alternative possibilities in my mind. Perhaps they're both correct, but it would seem to me that either one or the other is.
Possibility number one is that these groups are operating a bit like the condottieri of the Italian Renaissance, groups that could have fought each other but were actually trying to avoid inciting any casualties and would engage in demonstrations of strength in some other manner. That's one possibility.
The other possibility is that these are simply groups of brigands, to some degree. They started evolving into groups that really didn't have a cause except self-perpetuation.
What would be the case?